Autonomy of C1 + Display + Battery

[ManoShu]

I got a C1+ recently and i want to know how much i would have using a battery as power source, making the future project portable.
Here's the part list:

Code: Select all

Battery
20000mAh (actually 16000mAh) LiPo
http://produto.mercadolivre.com.br/MLB-696710438-bateria-20000-mah-tablet-37v-dltectoynavcitylenoxxmulti-_JM

Charger
PowerBoost 1000 Charger
https://www.adafruit.com/products/2465

Board
C1+
http://www.hardkernel.com/main/products/prdt_info.php?g_code=G143703355573

Display
5 inch HDMI LCD
http://www.dx.com/p/5-inch-hdmi-tft-lcd-touch-screen-shield-800-x-480-for-raspberry-pi-2-model-b-b-a-b-384212#.VktyAHarRQI

OR

ODROID-VU7
http://www.hardkernel.com/main/products/prdt_info.php?g_code=G144549683088


Input
IO Board / Keyboard / Controllers (Max 3)

Sound
USB Audio Adapter
http://www.hardkernel.com/main/products/prdt_info.php?g_code=G141629380416

Is there a way to determine how much time it gets before need to recharge?

[odroid]

Depends what software run on the C1+.
If it consumes around 1Amp, the battery can run around 15hours.
Average task may need 500mA, you can run it 30hours approx.

[ManoShu]

Initially, i am using Hardkernel's default C1+ image to run. Maybe later i will build my own kernel to strip down unnecessary parts.
The applications are still not done to the point of measuring consumption, but test using SDL rendering used ~10% of CPU, so i assume it will not use full processing power at all times.

The premises of operation on the project are most likely those:

• The display will be always on during use;
• The audio adapter will always be used;
• Forgot to add the Audio Amplifier (https://www.adafruit.com/products/1752) to the list so it adds ~20mA to total load;
• The applications will use SDL2 and FMOD libraries;
• At least one USB device (Keyboard/USB IO Board/Joystick) will be plugged at all times to operate the applications. However, up to 3 can be used at the same time;
• The minimum time on battery should be ~4hours, the more the better;

Based on the page of the PowerBoost board, it can supply up to 2000mA, so i am just making sure it will work before purchasing the additional parts.

[odroid]

I think all the items can be managed at 500~700mA probably except for the display.
What display do you consider?

[Laokoon]

This is what I've built recently:



I've used Waveshare 7" TFT LCD 1024x600 with touchscreen, cheap WiFi adapter, 4x18650 accu with 1A charging module and 5V step-up 1,2A module. All these parts I've put into 3$ plastic case. What I plan is to add resistor divider and connect it to ADC in order to check battery voltage with Python soft. It could also shutdown system automatically when voltage drops below 5% or something like this.

It is portable and not to heavy: weigts less than 700 grams. I didnt't measure how long it can operate on batteries yet.

[ManoShu]

I think all the items can be managed at 500~700mA probably except for the display.
What display do you consider?

After seeing that the VU7 will let the board's IO free, i will definitely use it instead of the DX one.

This is what I've built recently:



I've used Waveshare 7" TFT LCD 1024x600 with touchscreen, cheap WiFi adapter, 4x18650 accu with 1A charging module and 5V step-up 1,2A module. All these parts I've put into 3$ plastic case. What I plan is to add resistor divider and connect it to ADC in order to check battery voltage with Python soft. It could also shutdown system automatically when voltage drops below 5% or something like this.

It is portable and not to heavy: weigts less than 700 grams. I didnt't measure how long it can operate on batteries yet.

Very good casing!
My project would probably have a similar look to it.

[Laokoon]

I've checked how long this can stay on batteries and I'm not very happy. I've used 4x18650 accu which in theory should give me about 10Ah (2500mAh each). I measured the time and it was about 2h with Odroid running without any highly power consuming apllication like movie player or similar. So power consumpion is very high. I assume that mostly by LCD.
I've also had WiFi and audio USB sticks plugged and running.
I've assumed batteries voltages are 4.2V as 100% and 3.2V as 0% and measured it usind Odroid ADC through resistor divider.

[ManoShu]

Interesting, but correct me if i am wrong: based on your calculations it means the total consumption is 5000mAh (10000mAh source running for 2 hours)?

The display that you're using have some sort of brightness control?
Even then the VU7 specs says that it consumes 600mA; maybe WiFi/USB are using a lot of power too?

Even with that power hungry setup, a 20000mAh battery still holds up, but i wish it could last longer.

[Laokoon]

I removed batteries from old laptop packets so i'ts possible, that they don't have 2500mAh any more. But they are in a quite good condition since I'm able to load it to 4.2V.
Secondly I used step-up module between batteries and Odroid and the rest of stuff, it drains more amps than gives. Enyway this module can provide no more than 1.2A so the power consumption can't go beyond this limit on 5V side.
I was not able to reach technical sheet of my LCD panel but Waveshare suggests to use 2A power supply for it. It has no brightness control but it has backlight cut-off switch, which I actually don't use.

I have a lot of room in my case but it becomes less mobile if it weights 3kG due to additional batteries

[ManoShu]

Could you link to the step-up module that you used?
I hope the PowerBoost don't use much power by itself. I see that it's max output is 1.8A so that should be no problem.
The VU7 at least is being shown using the microUSB port for power, so i hope it will burn less battery.

[Laokoon]

ManoShu

Actually you can be right, I couldn't find the module at the site that I have bought it since it's discountinued there but then I've found this (it's in Polish):
https://elty.pl/pl/p/Przetwornica-napie ... 77-ADJ/257
which looks pretty the same as mine. This means that current provided by the module is 3A not 1,2 as I was informed buying this.
It's better to measure current at the output of the module, I'll let you know after i do that.

[Laokoon]

Ok, I've measured it. When it runs on "standby" it consumes 0.95A, doing some job like playing video up to 1.1A.
Surfing the net with Chrome consumes 1.2A. Weird.
Measured on the power plug.

[ManoShu]

Weird indeed. That means that your batteries are only giving 4000mAh?!
I am borrowing a 10000mAh portable battery to test only the board to see how much it will use in my case while the VU7 don't show up.

[bemnet4u]

All these parts I've put into 3$ plastic case.

May I ask where did you find this case? I am looking for similar setup and need a case to enclose my VU7, XU4 and few other parts.

Thanks

[Laokoon]

I play with electronics for years and I found a shop where I buy such cases years ago. Unfortunatelly this shop does not sell abroad and it's placed in Gdansk, Poland.
Please give me your whereabouts and we'll think how to send it to you

I've found producer (probably) of this cases:
http://www.sklep.cyfronika.com.pl/en_US/c/Plastic/210

You can check delivery conditions here:
http://www.sklep.cyfronika.com.pl/en_US/i/Delivery/11

[ManoShu]

Okay, i finally received all the parts that i needed.
The only major change was that i got a 3600mAh battery instead of the one i listed before, as i bought from a friend that just purchased it so it's brand new. This is a link to the page where he bought (it was local).

A quick run with the WiFi module 3 and Sound Adapter while playing a looping fullscreen Youtube video, consuming ~70% of CPU ran for just ~15 minutes before the PowerBoost activate it's "Low Battery" LED. I am aware that the draw is higher because it's converting 3.7 to 5 volts, but wow.

The project will not have WiFi, and probably will not use that much CPU (i hope). There's something that can be done to reduce the consumption with some loss of performance beside the CPU throttle option?

I can now test results based on multiple configurations (stand-by, high CPU, high WiFi usage,etc) later. Any other suggestion on a configuration to be tested is welcome.

[odroid]

Can you measure the power consumption?

[ManoShu]

Can you measure the power consumption?

Currently no, as i only have a basic multi-meter that can measure only up to 200mA continuously.
Waiting for a "Charger Doctor" to arrive (~3-4 days) so i can just leave it plugged on the USB port.